Endothelin-1 Elicits TRP-Mediated Pain in an Acid-Induced Oral Ulcer Model.

Oral ulcer is the most common oral disease and leads to pain during meals and speaking, reducing the quality of life of patients. Recent evidence using animal models suggests that oral ulcers induce cyclooxygenase-dependent spontaneous pain and cyclooxygenase-independent mechanical allodynia. Endothelin-1 is upregulated in oral mucosal inflammation, although it has not been shown to induce pain in oral ulcers. In the present study, we investigated the involvement of endothelin-1 signaling with oral ulcer-induced pain using our proprietary assay system in conscious rats. Endothelin-1 was significantly upregulated in oral ulcers experimentally induced by topical acetic acid treatment, while endothelin-1 production was suppressed by antibacterial pretreatment. Spontaneous nociceptive behavior in oral ulcer model rats was inhibited by swab applications of BQ-788 (ETB receptor antagonist), ONO-8711 (prostanoid receptor EP1 antagonist), and HC-030031 (TRPA1 antagonist). Prostaglandin E2 production in the ulcers was suppressed by BQ-788. Mechanical allodynia in the model was inhibited not only by BQ-788 and HC-030031 but also by BQ-123 (ETA receptor antagonist), SB-366791 (TRPV1 antagonist), and RN-1734 (TRPV4 antagonist). In naive rats, submucosal injection of endothelin-1 caused mechanical allodynia that was sensitive to HC-030031 and SB-366791 but not to RN-1734. These results suggest that endothelin-1 production following oral bacterial invasion via ulcerative regions elicits TRPA1-mediated spontaneous pain. This pain likely occurs through an indirect route that involves ETB receptor-accelerated prostanoid production. Endothelin-1 elicits directly TRPA1- and TRPV1-mediated mechanical allodynia via both ETA and ETB receptors on nociceptive fibers. The TRPV4-mediated allodynia component seems to be independent of endothelin signaling. These findings highlight the potential of endothelin signaling blockers as effective analgesic approaches for oral ulcer patients.

Neuroprotective effects of yokukansan, a traditional Japanese medicine, on glutamate-mediated excitotoxicity in cultured cells.

To clarify the mechanism of yokukansan (TJ-54), a traditional Japanese medicine, against glutamate-mediated excitotoxicity, the effects of TJ-54 on glutamate uptake function were first examined using cultured rat cortical astrocytes. Under thiamine-deficient conditions, the uptake of glutamate into astrocytes, and the levels of proteins and mRNA expressions of glutamate aspartate transporter of astrocytes significantly decreased. These decreases were ameliorated in a dose-dependent manner by treatment with TJ-54 (100-700 microg/ml). The improvement of glutamate uptake with TJ-54 was completely blocked by the glutamate transporter inhibitor DL-threo-beta-hydroxyaspartic acid. Effects of TJ-54 on glutamate-induced neuronal death were next examined by using cultured PC12 cells as a model for neurons. Addition of 17.5 mM glutamate to the culture medium induced an approximately 50% cell death, as evaluated by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. TJ-54 (1-1000 microg/ml) inhibited the cell death in a dose-dependent manner. Furthermore, competitive binding assays to glutamate receptors showed that TJ-54 bound potently to N-methyl-D-aspartate receptors, in particular, to its glutamate and glycine recognition sites. These results suggest that TJ-54 may exert a neuroprotective effect against glutamate-induced excitotoxicity not only by amelioration of dysfunction of astrocytes but also by direct protection of neuronal cells.

An inhibitory effect of cytokine-induced neutrophil chemoattractant on corticotropin-releasing factor-induced increase in locomotor activity.

To investigate whether cytokine-induced neutrophil chemoattractant (CINC) has an influence on corticotropin-releasing factor (CRF) in the central nervous system, the effects of intracerebroventricular (i.c.v.) injection of CINC on CRF-induced behavior were examined. Intracerebroventricular CRF injection produced an increase in locomotor activity, which was significantly reduced by i.c.v. injection of CINC. The intravenous injection of CINC did not alter CRF-induced locomotor hyperactivity. These results suggested that CINC has a functional antagonistic action on the response to CRF and may attenuate stress responses.

A second leukotriene B(4) receptor, BLT2. A new therapeutic target in inflammation and immunological disorders.

Leukotriene B(4) (LTB(4)) is a potent chemoattractant and activator of both granulocytes and macrophages. The actions of LTB(4) appear to be mediated by a specific G protein-coupled receptor (GPCR) BLT1, originally termed BLT (Yokomizo, T., T. Izumi, K. Chang, Y. Takuwa, and T. Shimizu. 1997. Nature. 387:620-624). Here, we report the molecular cloning of a novel GPCR for LTB(4), designated BLT2, which binds LTB(4) with a Kd value of 23 nM compared with 1.1 nM for BLT1, but still efficiently transduces intracellular signaling. BLT2 is highly homologous to BLT1, with an amino acid identity of 45.2%, and its open reading frame is located in the promoter region of the BLT1 gene. BLT2 is expressed ubiquitously, in contrast to BLT1, which is expressed predominantly in leukocytes. Chinese hamster ovary cells expressing BLT2 exhibit LTB(4)-induced chemotaxis, calcium mobilization, and pertussis toxin-insensitive inhibition of adenylyl cyclase. Several BLT1 antagonists, including U 75302, failed to inhibit LTB(4) binding to BLT2. Thus, BLT2 is a pharmacologically distinct receptor for LTB(4), and may mediate cellular functions in tissues other than leukocytes. BLT2 provides a novel target for antiinflammatory therapy and promises to expand our knowledge of LTB(4) function. The location of the gene suggests shared transcriptional regulation of these two receptors.

A new technique applicable to pediatric laparoscopic surgery: abdominal wall 'area lifting' with subcutaneous wiring.

BACKGROUND: Recently, the authors developed a unique method of laparoscopic surgery without pneumoperitoneum: "area lifting of the abdominal wall with subcutaneous wiring." METHODS: In this gasless procedure, the anterior abdominal wall is pulled upward by a pair of wires placed subcutaneously and held by thick sutures for "hanger lifting." Simultaneous lifting of a pair of subcutaneous wires across the abdomen, produces a wide, roof-shaped intraabdominal space sufficient for laparoscopic surgical procedures. The practical aspects of this gasless technique, as well as the authors' limited experience with this method in 24 children, ranging from 8 days to 15 years of age is presented. These children have had various pathologies including splenomegaly, rectal prolapse, ovarian cyst, gall stone, adrenal neuroblastoma, and abdominal wall abscess. CONCLUSIONS: Gasless laparoscopic surgery with double subcutaneous wiring is safe for children including neonates and those with respiratory compromise because all operative procedures are performed under normal abdominal pressure. Because of the highly elastic abdominal wall musculature inherent in children, this selective area lifting of abdominal wall creates a relatively larger peritoneal volume than in adults.

Activation of macrophages by crude polysaccharide fractions obtained from shoots of Glycyrrhiza glabra and hairy roots of Glycyrrhiza uralensis in vitro.

Many plant polysaccharide fractions have been reported as immunomodulatory agents. However, sometimes the possibility of contamination with bacterial lipopolysaccharide (LPS), a potent B cell mitogen and immune modulator, is discussed. In the present paper, we investigated the effects of crude polysaccharide fractions obtained from the shoot and hairy root of Glycyrrhizae sp. on murine peritoneal macrophage function, in order to clarify whether plants grown under aseptic conditions produce immunomodulatory polysaccharides. All crude polysaccharide fractions induced nitric oxide production by murine peritoneal macrophages in vitro. Chemical analysis revealed that LPS-like molecules were not present in all preparations. These results suggested that shoot and hairy root biosynthesized polysaccharides that could stimulate macrophages de novo.

The role of crude polysaccharide fractions on the mitogenic activity by Shosaikoto.

Shosaikoto, which is one of the Japanese and Chinese traditional herbal medicine mixtures, has several immunomodulating activities. Especially, Shosaikoto is a potent polyclonal B cell mitogen in vivo and in vitro. In order to characterize the active substances for mitogenic activity, Shosaikoto was fractionated by means of ethanol precipitation to give two fractions, called ethanol-precipitate (EP) fraction and ethanol-soluble (ES) fraction. The EP fraction consisted mainly of polysaccharides and showed significant mitogenic activity. The ES fraction consisted of low molecular compounds and did not show the activity in vitro. The EP fraction of hot water extracts of Glycyrrhizae Radix and Bupureuri Radix showed the activities, and the ES fraction of a hot water extract of Glycyrrhizae Radix and all fractions of hot water extract of Scutellariae Radix showed the cytotoxicity. These results suggested that the crude polysaccharide fractions could play an important role in the mitogenic activity by Shosaikoto.

The effects of crude polysaccharide fractions of 4 kinds of kampo-hozai administered orally on nitric oxide production by murine peritoneal macrophages.

In order to characterize the pharmacological role of the crude polysaccharide fraction in kampo-hozai, we chose 4 kinds of kampo-hozai, Shosaiko-to, Daisaiko-to, Hachimi-jio-gan and Hochu-ekki-to, and studied the effects of their crude polysaccharide fractions on nitric oxide (NO) production by 3% thioglycollate-induced murine peritoneal macrophage. Oral administration of these fractions for 7 d augmented lipopolysaccharide (LPS, 0.1-10 micrograms/ml)-induced NO production by peritoneal macrophages. These results suggest the possibility that a crude polysaccharide fraction affect the macrophage function in most kampo-hozai.

Effect of karasurin-A on nitric oxide production by murine macrophages and mitogenic response of murine splenocytes in vitro.

We studied the effect of karasurin-A, a type-I ribosome-inactivating protein (RIP) isolated from fresh root tubers of Trichosanches kirilowii MAX. var. japonica KITAMURA, on the mitogenic response of murine splenocytes and nitric oxide (NO) production by murine peritoneal macrophages in vitro. Karasurin-A inhibited the lymphocyte proliferation by LPS, ConA and PHA and NO production by LPS at non-cytotoxic concentrations (10-1000 ng/ml for splenocytes and 10-100 ng/ml for macrophages, respectively). These data suggest that karasurin-A has immunosuppressive activity in vitro.

The role of a crude polysaccharide fraction in the macrophage activation by "Shosaikoto".

Oral administration of Shosaikoto (1.4g/kg) enhanced phagocytosis of casein-induced murine peritoneal macrophages and nitric oxide (NO) production of thioglycilate broth-induced murine peritoneal macrophages. To clarify the kind of compounds are responsible for this augmentation of macrophage function, ethanol-precipitation was carried out to produce two fractions: one of ethanol-precipitates (EP) and one ethanol-soluble (ES). The EP fraction consisted of polysaccharide and showed enhancement of phagocytosis and NO production comparable to Shosaikoto's. On the other hand, the ES fraction consisted of low molecular compounds and did not affect macrophage function. These results suggest a crude polysaccharide fraction plays an important role in Shosaikoto's macrophage activation.

The effects of 18 alpha,beta-glycyrrhetinic acid on the hormonal induction of tyrosine aminotransferase in rat primary cultured hepatocytes.

The effects of 18 alpha,beta-glycyrrhetinic acid (18 alpha,beta-GA) on the hormonal induction of tyrosine aminotransferase (TAT) in rat primary cultured hepatocytes were investigated. Dexamethassone or glucagon used alone caused an increase in enzyme activity, and in combination their effects were additive. In the 18 beta-GA hepatocytes pretreated for 6 h, the dexamethasone-induced increase in the enzyme activity was slightly reduced in a dose-independent manner, and the glucagon-induced increase and the combined effects of these two inducers were significantly reduced in a dose-dependent manner. On the other hand, 18 alpha-GA, which was the isomer of 18 beta-GA, exerted no influence on the hormonally mediated increase in enzyme activity. Moreover, 18 beta-GA reduced the glucose release induced by glucagon in a dose-dependent manner and 18 alpha-GA did not. These results suggested that 18 beta-GA reduced the glucagon-mediated cell response in rat hepatocytes.

Evaluation of long-term results of Caroli's disease: 21 years' observation of a family with autosomal "dominant" inheritance, and review of the literature.

A 5-year-old girl underwent laparotomy in 1972 because of hepatomegaly and mottled radiopacities shown by cholangiography. Polycystic segmental dilatation of the intrahepatic bile ducts, typical of Caroli's disease, was found. Thereafter she remained in good health for over 21 years with careful medical management. In 1972 mottled radiopacities of the hepatic parenchyma were also demonstrated by cholangiography in her 9-year-old brother, who, however, remained asymptomatic until hematemesis due to esophageal varices suddenly occurred in 1993. At the time of the pre-operative evaluation for esophageal transection, his condition was definitively diagnosed as Caroli's disease. Their father was in good health, but in 1993 was shown by CT to have the same disease. The mode of inheritance is likely to be autosomal dominant, although Caroli's disease or congenital hepatic fibrosis is generally considered autosomal recessive (McKusick number 263200) (1). If we had not examined the father, this particular family would have been accepted as an example of autosomal recessive inheritance. We suggest that further family studies are needed to exclude the autosomal dominant mode of inheritance, and that at least some of the recessive cases in the literature are, in fact, autosomal dominant. Well-documented cases of "classical" Caroli's disease in the literature were reviewed with special reference to the long-term results. In addition, an international questionnaire aimed at establishing the further clinical course of the patient was sent to authors who reported cases after 1968.(ABSTRACT TRUNCATED AT 250 WORDS)

[Cardiopulmonary exercise test in patients with DDD pacemaker: report of two cases with increased exercise capacity by decreased ventricular tracking limit rate setting].

We reported 2 patients with complete A-V block with a DDD pacemaker whose exercise capacity was increased by decreased ventricular tracking limit rate setting (VTL) of their pacemakers. Cardiopulmonary exercise test was used for estimating exercise capacity. Case 1: A 15-year-old girl complained of fainting. Her electrocardiogram (ECG) revealed complete A-V block (atrial rates 100/min, ventricular rates 39/min). After implantation of a DDD pacemaker and the VTL setting at 152/min, her bradycardia disappeared, however, she complained of dyspnea after a few minutes' walk. We performed symptom-limited cardiopulmonary exercise test with a motor-driven treadmill. When the pacing rate reached VTL (152/min), ECG suddenly changed to approximately 2:1 pacing (80/min) and the patient complained of dyspnea. Concomitant rapid increases in VE, VCO2 and RQ suggested that dyspnea was caused by the marked change in pacing rates on VTL. With the lowered VTL (110/min), there was no rapid increase in VE, VCO2 and RQ, and dyspnea subsided when the pacing rate reached VTL. At the same time, the peak VO2 and exercise time were increased by 15% and 8%, respectively. Case 2: A 47-year-old man complained of syncope. His ECG revealed complete A-V block (atrial rates 100/min, ventricular rates 33/min). After a DDD pacemaker implantation (VTL: 150/min), he experienced dyspnea while walking up the stairs in his office. Like in Case 1, when the VTL was lowered from 150/min to 110/min, both the peak VO2 and exercise time were increased by 11%.(ABSTRACT TRUNCATED AT 250 WORDS)

[Medical and surgical treatment for patients with dissecting aneurysms of the aorta].

The medical and surgical treatment of 96 patients of dissecting aneurysms was reviewed. There were 42 patients with Stanford type A dissecting aneurysms, 19 of whom received medical treatment and 23 of whom had surgical treatment. Among 54 patients with Stanford type B dissecting aneurysms, 24 had medical and 30 had surgical treatments. The treatment results and the long-term outcomes were studied using the Kaplan-Meier method, categorizing the subjects in non-survivor (in-hospital) and survivor groups. The results indicated that those with surgical treatment had a higher survival rate (75%) in the early post-operative course, for both type A and type B aneurysms. However, the long-term outcome of the survivor group was not different between type A and type B aneurysms regardless of type of treatment. Fifty-six percent of cases with type A aneurysms with serious complications survived by medical treatment alone, and no intimal tears were visualized on angiogram. Therefore, it was suggested that, in patients who had no angiographically defined intimal tears in the acute phase, medical treatment may be more effective, even for type A dissecting aneurysms.